The study focuses on reliable reverse engineering of electron-beam deposited TiO2/SiO2 coatings. It is known that optical constants of evaporated TiO2 films are dependent on deposition conditions and may vary from layer to layer. Also, the nominal optical constants, used during the theoretical designing, may differ from the actual optical constants of coating layers, determined based on characterization of thicker single layers. Typically, post-production characterization of e-beam evaporated coatings is based on spectral photometric or/and ellipsometric data measured ex-situ. The study reports a new reliable algorithm that allows reliable estimation of layer thicknesses and optical constants based on ex-situ measurements. The reliability of the results is verified using a specially produced unique set of samples including single layers identical to the ones included in the multilayer sample. The obtained results, based on the photometric and ellipsometric data, are in correspondence with each other. The algorithm delivers practical results and avoids overfitting.
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